[Diagnosis of placenta previa accreta by two dimensional ultrasonography and color doppler in patients with cesarean section].

OBJECTIVE: To determine the accuracy of two dismensional sonography and color doppler in diagnosing placenta previa accreta in patients with previous cesarean section. METHODS: Forty-one patients with previous cesarean sections were confirmed to have partial or total placenta previa in the current pregnancy and were given ultrasound examinations after the 28th week of gestation. Specific ultrasound features of the placenta and its interphase with the uterus and the bladder for placenta accreta were checked by two-dimensional ultrasonography and color Doppler. All the patients were traced until delivery. The golden standard in diagnosis was the intraoperative finding and the pathologic exam. RESULTS: Twenty-two patients had ultrasonographic evidence of placenta previa, 20 of which were later confirmed placenta previa accreta intraoperatively. Nineteen patients had no ultrasound evidence of placenta previa, and 1 of which was later confirmed placenta previa accreta. The sensitivity and specificity of antenatal ultrasound diagnosis of placenta previa accreta were 95.24% and 94.74% respectively. The most prominent feature to suggest placenta accreta in twodismensional sonography was the presence of multiple lakes that represented dilated vessels extending from the placenta through the myometrium. The most prominent color Doppler feature was the presence of interphase hypervascularity with abnormal vessels linking the placenta to the bladder, and the rate was 95.24%. CONCLUSION: Placenta previa accreta can be diagnosed made with a thorough two dimensional ultrasonographic and color Doppler examination in patients with previous cesarean scar and placenta previa.